Garden with the masters

Kathy Fuller/The ArgusLearn how to make an eco roof at the Washington County Fair at the Master Gardeners demonstration garden. Other workshop topics are worm composting, adaptive gardening and seed starting.

Fair time is a busy time for the OSU Extension Service Master Gardeners in Washington County. And they are delighted.

The fair is prime time for the Master Gardeners to show off their crown jewel — the demonstration garden — located right on the fairgrounds next to the Hillsboro Armory.

But more important for them is the opportunity to share their vast and varied knowledge of gardening with the public.

Their newest project is an eco-roof, a “living roof” atop a garden shed.

Eco-roofs, says master gardener Bill Klug, are a popular issue in gardening right now. In addition to being more appealing to the eye than a traditional roof, eco-roofs are friendly to the environment. When it rains, an eco-roof, which is built in six layers, absorbs the water. Traditional roofs channel water right into gutters and on down the storm drain. “The water is retained in the soil and used by the plants,” Klug said.

The trick to building an eco-roof, Klug said, is to make sure it’s built strong and reinforced properly to hold the extra weight of soil, water and plants. “I always tell people to consult an engineer or architect,” Klug said.

Klug will host a workshop at 2:15 p.m. Friday, explaining more about eco-roofs. The roof in the demonstration garden is built at eye level, Klug said, so folks can see it and touch it. One side shows the finished product, the other shows the six layers that make up an eco-roof.

While Klug chose to plant sedum and use decorative rock, he said an eco-roof could grow almost anything.

“Each (type of sedum) has a different texture and a different bloom time. It’s visually appealing,” Klug said. And sedum grows quickly. “Next year at this time, you probably won’t see the rocks.”

The master gardeners received two $500 grants, one from the Hardy Plant Society of Oregon and one from the Aloha Garden Club. They pitched in another $500 and were one their way to an eco-roof for their own use and for teaching others. In addition to Klug’s workshop, gardeners of all ages and abilities can learn about a variety of gardening subjects during the four days of the fair — from outdoor composting to composting with worms; from growing tomatoes to growing potatoes; and from carnivorous plants to raspberries.

There will also be two workshops on adaptive gardening. Everyone, regardless of physical ability, can continue to reap the benefits of gardening. Learn how.

The demonstration garden will also be open for self-guided tours from 10 a.m. to 7 p.m. all four days of the fair, from Thursday, July 28, through Sunday, July 31.

The garden is also open 9 a.m. to noon every Tuesday during the growing season and is staffed with Master Gardeners eager to answers gardening questions.